Boiler



Aug. 18, 1931. v, STEVENS 1,819,134

BOILER Filed Nov. 12. 1928 2 Shets-Sheet 1 l i l JNVENTOR.

ATTORNEY Aug; 18, 1931. H. v. STEVENS BOILER Filed Nov. 12, 1928 2Sheets-Sheet 2 Q 1 V o o O m omo oomo 1 0 0 0 0 0w 1 0 0 wow Q Q O Q Q 0v I 0 Q N. O 0

2 I/Ig ENTOR.

@TTO'RNEY Patented Aug. 18, 1931 PATENT OFFICE HENRY V. STEVENS, FTOPEKA, KANSAS BOILER Application filed November 12, 1928. Serial No.318,818.

My invention relates to boilers and more particularly to locomotiveboilers, the principal objects of the invention being to eifect fuelsaving by providing increased active (heating surfaces in the boiler, toeffect circulation through all parts of the boiler, thereby eliminatingdormant zones, to effect a greater ,steaming capacity and to provideboiler struc ture minimizing maintenance costs as well as the hazards ofboiler failure due to low water. In accomplishing these and otherobjects of the invention, I have provided improved details of structure,the preferred forms of which are illustrated in the accompanyingdrawings, wherein:

Fig. 1 is a longitudinal vertical sectional view through the rear end ofa locomotive boiler constructed in accordance with my invention. Fig. 2is a cross sectional view through th boiler on the line 22, Fig. 1.

Fig. 3 is a horizontal sectional-view through the boiler on the line 33,Fig. 2.

Fig. 4 is a detail sectional view through a modified form of boiler.

Referring more in detail'to the drawings:

1 designates a locomotiveboiler comprisingv a barrel portion 2 and afire box portion 3 comprising a back sheet 4, a roof sheet 5 and casingsheets 6 and 7 constituting the outer walls of the fire box. The innerwalls of the fire box comprise a crown sheet 8, side sheets 9 and 10 anda door sheet .11 spaced from the corresponding sheets of the boiler anda flue sheet 12 supporting the rear ends of the fire tubes 13. p t

The casing sheets and the back sheet and an vouter throat sheet 14 arepreferably connected :with a mud ring 15 which encircles the lower partof the fire box as in standard boiler pracgtice, the inner and outersheets being spaced to provide water legs at the sides and door end ofthe fire box designated 16, 17 and 18 re-' spectively and a steamingspace 19 above the crown sheet of the fire box.

The bottom of the fire box, in ordinary coal {burning engines, is closedby the grates and ash pan, or in oil burning locomotives and locomotivesconverted from coal burners, the

bottom of thefire boxes are covered with refractory material and noattempt is made to utilize the heating surface in the bottom of. thefire box and thereby utilize the maximum heat ofcombustion. 1 I

In order toutilize heat of combustion in the bottom of the fire box, Ihave constructed a water table under the entire area of the fire box andcommunicating with the water legs of the boiler thereby entirelysurrounding the area of the fire box with water and utilizing the entireactive heating surface of the boiler as well as greatly increasing thewater holding capacity. 7

In carrying out this object I curve the side sheets 9 and 10 of the firebox inwardly above the mud ring as at 20 and then downwardly below themud ringas at 21 to form side shelves and again inwardly as at 22 toform a floor and provide a solid bottom sheet 23 enclosing the entirearea of the fire box, the curved bottom providing the deepest possiblecombustion chamber for the fire box as Well as presenting curvedsurfaces to the fire. Fixed to the inner sides ofthe mud ring is asimilarly curved bottom sheet 24 spaced from the sheet 23 to provide awater space 25 which communicates with the water legs above the mudrings as-at 26. At the for ward end of the fire box the sheets 23 and 24are curved" upwardly as at 27 and28 adjacent the burner opening29 to"form a burner wall and then forwardly as at 30 :toconnect with theinner throat sheet 31 and the mud ring 15 respectively to provide ahollow front shelf portion so that the water space-25 also communicateswith the barrel of the boiler through a throat 32 formed by the throatsheets. The sheets 23 and 24 connect with the back and door sheets in amanner similar to the side sheets by sweeping curves 33 and 34 forming areal shelf. 1 In orderto supply ai for supporting combustion in the firebox, I provide the bottom sheets at each side of the fuel nozzle 35 witha plurality of air-conduits 36 comprising pipenipples 37 welded into thesheets to make a water tight joint. Air may also be supplied through adoor or hopper opening 38 formed in the bottom of thefire box in frontof the nozzle 35.

It is also desirable to cover a portion of the bottom of the fire boxand a portion of the door sheet in front of the burner with fire brick39 to provide an incandescent surface against which the flame of theburner is directed to aid in the burning of the fuel.

As before stated it is also an object of the invention to circulatewater throughout all parts of the boiler and in accomplishing thiscirculation I employ the therihosiphonprinciple and utilize a pluralityof water conveying conduits extending through the hottest zone of thefire box and communicating the water table with the steam space 19 abovethe crown sheet so that water passing through the conduitsis quicklyheated and converted into steam which isdisplac'ed by the cooler waterin the water table thereby producing a' siphon effectthrough theconduits.

In the present illustration I employ three water bonduits designated 40,41, and 42 respecti-vely, theouter conduits 40 and 4-2 connecting theside shelf portions of the water table withthe side portions of thecrown sheet and the conduit 41, the central part of the front shelfportion of the water table with the central portion of the crown sheet.The-inlet 48 to the central conduitis positione'd forwardly withrelation to the inlets 4st and 4-5 of the other conduits so as to notinterfere with combustion space in the fire box and 'at the same timeallowing for an arrangement whereby all the conduits receive direct heatof the flame and the prodnets of combustion before they pass out throughthe firetubes of the boiler.

Iihe water conduits are preferably rectangular in cross section and arefunnelshaped from the bottom up so as to provide for expansionof thewater as it is converted into steam and prevent violent spouting ofwater into the steam compartment above the crown sheet. e v

The conduits are preferably constructed of boiler plate and areflangedat their upper ends as at46. and ,welded to the edgesof openings47 provided in the crown sheet. The lower ends of the conduits areconnected with the inner sheet 23 inlike manner although I prefer toprovide an expansion curve '48 in the lower flange of the conduits. Theconduits are internally reinforced with stay bolts 49 and the upperflanges 46 of condiiitsare suspended by stay bolts 50 from the outercrown sheet similar to the support of the-lire boa crown sheet as instandard boiler practice, 7

'Suitable'cl ean out plugs designated '51 may b e po s'itioned above andbelow the conduits tfo provide for 'cleaning'scale deposits and the likefrom the conduits andthe interior of the boiler. H v V Blow off cocks'52 and 53 m'ay'also be provided in the lower sheet of the watertablefor removing mud and sediment which collects therein.

In some instances it may be desirable to eliminate the mud ring as shownin Fig. 4; thereby reducing the weight of the boiler, and in thisinstance the outer table sheet will be connected to the casing boilersheets in rounding curves similar to the inner sheet connections withthe side sheets.

Assuming v that the boiler constructed as described is filled to a levelabove the crown sheet, the water circulation is as follows:

Water in the conduits is heated almost as soon as the fuel in the firebox is ignited starting circulation of the water from the water tableinto the water carried on the top of the crown sheet. The cooler waterin the water legs then replenishes the water in the water tablecontinuing the circulation.

The water in flowing throughthe conduits which is in the hottest part ofthe life box, starts steaming almost immediately, causing the cyclingofwater through the conduits and down the water legs through the tableand back through the conduits producing a violent pumping action throughthe conduits, causing the circulation of the water from the front end ofthe boiler through the throat and into the table whereupon it passesthrough the conduits and .is heated and re-' circulated so that water inall parts of the boiler is brought into direct contact with the hottestzone of the fire bo'x, thereby equaliz ing temperature of water in everypart of the boiler and minimizing boiler maintenance by reducing boilerstresses due to diiferences in temperature. i

Attention is also directed to the fact that the pumping action of thewater through the conduits reduces boiler hazards. In case the waterlevel of the boiler is allowed todrop below the crown sheet the umping acti'on throws water over the crown sheet in a fountain eifect keepingthe crown sheet wet all times and prevents damage to the crown sheet. v

It is ap'parenttha't I have provided a boiler utilizing all of theheating surface of the fire box and due to the water conduits Ihaveprovided for complete water circulation in all parts of the boilerthereby increasing the steamlng. capacity as well as reducing the timerequired to br'ing'the boilerto the "steaming point resulting in moreeconomic lo'coino tive operation. The better and quicker steamingqualities also allows higherspeeds on heavy grades with'o tflu'ctuationof, the steam pressure as well as p ermit'tinga lighter fire in ordinaryboiler operation.

What I claim and desire to secure by Letters Patent is: n I I 1. Inaboiler including a fire box, water legs at the sides of'the fire togawater table forming 1 ,116 bottom or the fire tax and cum-- prisingshelfportions'cnall sides or the life box directly communicating withthe water legs, and a floor portion positioned below the shelf portionsand cooperating with the shelf portions to provide a fuel cmbustionchamber.

2. In a boiler including a fire box, water legs at the sides of the firebox a water table forming the bottom of the fire box comprising integralside shelf portions on all sides of the fire box directly communicatingwith the water legs, and a floor portion positioned below the side shelfportions and cooperating with the shelf portions to form a combustionchamber.

3. In a boiler includinga fire box and water legs at the sides and endof the fire box, a water table forming the bottom of the fire box andcomprising side shelf portions directly communicating with the waterlegs, an integral rear shelf portion, and a floor portion integral withthe side portions and cooperating therewith to form a fuel combustionchamber in the water table below the water legs.

4,. In a boiler, a fire box, water legs at the sides and end of the firebox, a water table directly connecting the water legs, a fuel combustionchamber formed by the upper surface of the water table, a conduitextending through the fire box and communicating with the water tableand the Space above the fire box for circulating water surrounding thecombustion chamber upwardly through the conduit for discharge above thefire box.

5. In a boiler, a fire box, water legs at the sides and end of the firebox, a water table communicating with the Water legs and having adepressed portion to form a fuel combustion chamber, a conduitcommunicating with the depressed portion of the water table and a partof the boiler above said water table and extending through the fire boxto circulate water from the depressed portion of the water table.

6. In a boiler including a fire box and water legs at the sides and endof the fire box, a water table communicating with the lower ends of thewater legs comprising a substantially central depressed portion forminga fuel combustion chamber and shelf portions connecting the depressedportion with the water legs, and conduits communicatin with the shelfportions and a part of the oiler above said shelf portions and extendingthrough the fire box to circulate water by thermosiphonic action fromthe water table.

7. In a boiler, a fire box comprising an inner casing including door,flue and crown sheets, side sheets connecting the first named sheets andhaving their lower edges curved inwardly, downwardly and again inwardlyto form the bottom of the fire box and a central fuel combustionchamber, and an outer casing spaced from the inner casing to form awater space surrounding the inner casing including the fuel combustionchamber.

8. In a boiler including a fire box and water legs at the sides and endof the fire box, a water table communicating with the water legs andforming the bottom of the fire box, a burner wall formed in the watertable and having a burner opening therethrough, and a burner extendingthrough the opening.

9. In a boiler including a fire box and water legs at the sides and endof the fire box, a water table comprising spaced sheets forming thebottom of the fire box and providing a water space communicating withthe water legs, flash and burner walls formed by said sheets to providea fuel combustion chamber, a burner extending through the burner wall,and refractory material lining the flash walls for receiving the flamefrom the burner and maintaining temperature of the combustion chamberabove the combustion point of the fuel admitted to the burner.

10. A boiler including a fire box, water legs at the sides and end ofthe fire box and a barrel portion having a throat, a water tabledirectly connecting the water legs and the throat comprising peripheralshelf portions and a central depressed portion forming a combustionchamber, and air jets extending through the shelf portions at the sidesof the combustion chamber for admitting combus- Eon-supporting air tothe combustion cham- 11. A boiler including a fire box, water legs atthe sides and end of the fire box and a barrel portion having a throat,a water table directly connecting the water legs and the throatcomprising peripheral shelf portions and a central depressed portionforming a combustion chamber, air jets extending through the shelfportions at the sides of the combustion chamber for admittingcombustion-supp0rting air to the combustion chamber, and conduitsextending through the fire box and communicating with the shelf portionsand with the boiler above said shelf portions for circulating water fromthe depressed portion of the water table to a point above the shelfportions.

In testimony whereof I affix my signature.

HENRY V. STEVENS.

